SZÉKELY ENGINEERING
Tom Székely, P.E., LEED AP

EXPLANATIONS & EXAMPLES - Vol. 6, No. 1
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January 3, 2006

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The Shareholder/Unit Owner Board Member Survival Manual, or, Engineering for Dummies – Part 3

 

So, what was this I mentioned two issues ago about Building Code requirements for domestic hot water availability? Well, long before anybody thought of anything like Energy Conservation Codes, Reference Standard RS-16, Plumbing and Gas Piping, to the Building Code of the City of New York laid down requirements for temperature maintenance in hot water supply system piping in buildings four or more stories in height, or where the most distant hot water tap was more than 50 feet worth of piping from the hot water source.

 

In the old days, this used to be done almost always via a recirculating pump controlled by a temperature sensor near the end of the hot water supply main.  Nowadays, it’s not infrequently by the use of electrically heat tracing the supply main to maintain a minimum water temperature of 100 degrees F, as the latter consumes less energy than the former.

 

So if this wasn’t done as an energy saving measure (and one does save energy by keeping water warm rather than letting it cool and reheating it), why was it done?  Anyone who lives in, or has been to, a single family home knows that one can wait forever for hot water to come out of a tap the first thing in the morning, and even at other times during the day if there is not much use of hot water.

 

All those who save the cold water coming out of the tap until it gets hot, raise your hands. . .    I thought so.  Actually, so did the Code Authorities.  Throwing away potable water, especially during times of drought is counterproductive at best.

 

So why am I making an issue of the obvious?  Because I can’t tell you how many brownstones and apartment buildings I’ve been in where a hot water recirculation system does not exist, or if it exists, is inoperative, or, to cite a sometimes seen perversion, where the hot water recirculation pump runs constantly.

 

I have said over and over again that Building Systems Engineering is not Rocket Science, and one would expect, therefore, that operation and maintenance of those systems should be something which is effected with minimum fuss and reasonably good outcome.  I believe the apt locution in this case is “dream on.”

 

What is it about Co-op Boards and Conversion Plans which causes substantial money to be expended on, or to be reserved for, things like lobby and corridor redecoration, and maybe (but only if the elevators are downright unreliable) elevator upgrades, but things like refurbishing and maintaining the rest of the building’s mechanical and electrical systems are only addressed after little things like pump failures or electrical fires?

 

Well, part of it is the fault of people like me for not educating people as to the importance of such, which is why I’m writing this. 

 

Another part of the problem may be that there is no regular preventative maintenance plan budgeted for which has the systems inspected at least once a year.  I say at least once a year because in climates like ours, it makes sense to do a pre-winter inspection to check heating systems and a pre-summer inspection to check cooling systems.  A lot of this can, and probably should be, done via service contracts with reputable Contractors with whom the Board is comfortable, but there should probably also exist some mechanism whereby the building superintendent reports to the Board at least once a year, which could be satisfied via an oral report at one Board meeting.

 

In many larger buildings which have a design professional on retainer, one might want to consider a yearly inspection and report by the design professional on the condition of the building’s systems.  I mean, you’ve already got them to review plans of proposed renovations.  Why not have them help you stay ahead of things? Some buildings already do this (I hope).

 

The point behind all of this is that addressing maintenance via emergency repair rather than inspection  and preventative maintenance, is a lot like the aphorism about there never being enough money to do something right, but always enough money to do something over.

 

OK, that about does it for the explicitly mentioned “gotchas” of two issues ago, but what about the pump failures and electrical fires I brought up at the top of this column of text?  I mean what causes such things, and how can they be avoided?

 

To start with pump failures, such is usually a non-issue unless one has an older building with toilets below the level of sewer lines in the street, or a building tall enough to require a roof tank to provide adequate water pressure for upper floors and/or sprinkler/standpipe fire reserve.

 

In the natural world, weathering wears down mountain ranges over eons. Machinery wears out rather more quickly largely because of two things, which are really the same thing: heavy duty operation and high temperatures.  In moving equipment, the former results in the latter, and even when below the level of human perception, mechanical wear’s heat effects change at a rate exponentially faster than  that of natural processes. 

 

Think about it. The motors which drive pumps and other machinery usually turn at  a nominal 1800 or 3600 rpm.  A car at highway speeds probably turns between 1500 and 2000 rpm, and if driven 25,000 miles a year, it’s about equivalent to two weeks of continuous operation.

 

I’ve seen pumps whose bearings were leaking so badly the pump room would have become a swimming pool in short order were the ear-splitting racket which issued forth not of such magnitude as to disturb the dead.  The good outcome in such cases is when the bad bearings cause the drive motor’s overloads to trip, and no one above the sixth floor has any water.

 

Electrical fires are another issue, and the thing that needs to be internalized is that fuses and circuit breakers are only really effective against short circuits, and that while they offer some protection against low-level overloads, one can’t rely on such for fire prevention. In fact, one needs ground-fault interrupters for such, which I may discuss in a future issue.

 

Electrical wiring in prewar buildings, while not in great shape in feeders and receptacle circuits, is absolutely shot at ceiling lighting outlets where over fifty years of being cooked by the heat of light bulbs has turned flexible rubber or varnished cambric insulation into a brittle covering which disintegrates at the slightest touch. 

 

There are still buildings in this city originally lit by gas lights, which were electrified via the pulling of electrical wiring into existing gas piping, which has close elbow bends of such sharp radius as to have done the wiring insulation no good at all when the wire was pulled into the pipes. Incipient ground-fault, anyone?

 

Many ceiling light fixtures are still sold with hangers able to support them from old gas pipes, and I have witnessed removal of a pipe cap which retained such a fixture  hanger to the whoosh of natural gas.

 

That is, even when separate armored cable runs comprised the electrical wiring, abandoned gas branch piping which supported ceiling fixtures and associated junction boxes, was never disconnected from the gas piping risers and mains.

 

“It’s a jungle out there.”  Let’s be careful.

 

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